class Solution {

    public boolean isSameTree(TreeNode p, TreeNode q) {

        if(p == null&&q!=null || p != null && q == null) {

            return false;

        }

        if(p==null&&q==null) {

            return true;

        }

        if(p.val!=q.val) {

            return false;

        }



        return isSameTree(p.left,q.left)&&isSameTree(p.right,q.right);

    }

}



